Cascade Microtech Pyramid Probes - Manual (Page 7)

PN 153-691-2 www.cascademicrotech.comI Pyramid Probes: Used Core Inspection• 7
4. Inspect the core using the 50x objective. The primary goal at this magnification is to inspect the surface of the probe tip.
Beams
Are there any cracked beams?
Cracked beams can be waived by Engineering if they are a
redundant contact such as ground or power, or if they still have
electrical continuity.
Is beam slope greater than 10μm?
The probe tip is near the end of its life. Contact Engineering.
See the Pyramid Probe Core User Guide for more details on measuring beam slope.
Is there beam slope throughout all beams?
Beam slope throughout may indicate one of the following:
• Too much overtravel
• End of life
Is the beam slope isolated?
Isolated beam slope can indicate one of the following:
• Particle hit
• Mishandling
• Stepping off wafer
Inspection Area Criteria
Probe Tips
Is there any organic buildup or fibers on tips?
Fibers are not acceptable on used probe tips.
Used cores will have small amounts of organic contamination from probing or cleaning that might not be
completely removed by off-line cleaning.
To remove contamination, see the procedure in Pyramid Probe Cores Off-line Cleaning With Brush.
Is there any metal present on the probe tips?
Metallic buildup on the tips is acceptable if the core passes electrical test.
If there is aluminum or solder contamination covering more than 25% of the probe tip surface, provide
feedback to Engineering to evaluate the online cleaning parameters and the cleaning film.
Are the probe tips textured?
Probe tips for gold pads do not need texture, but can have a textured tip surface.
Probe tips for probing all other metals, must have texture on 25% of the tip surface.
Do the probe tips meet height and diameter dimensions?
For used cores, the criteria for tip height is to pass functional test.
For used cores, the criteria for tip diameter is device-specific to the passivation opening.
Do adjacent probe tips have a height difference greater than 2μm?
A height difference greater than 2μm on a used core is acceptable if electrical contact is made at production
overtravel.
Pyramid Probes: Used Core Inspection